crypto/algif_aead.c

   1 /*
   2  * algif_aead: User-space interface for AEAD algorithms
   3  *
   4  * Copyright (C) 2014, Stephan Mueller <smueller@chronox.de>
   5  *
   6  * This file provides the user-space API for AEAD ciphers.
   7  *
   8  * This file is derived from algif_skcipher.c.
   9  *
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms of the GNU General Public License as published by the Free
  12  * Software Foundation; either version 2 of the License, or (at your option)
  13  * any later version.
  14  */
  15
  16 #include <crypto/internal/aead.h>
  17 #include <crypto/scatterwalk.h>
  18 #include <crypto/if_alg.h>
  19 #include <linux/init.h>
  20 #include <linux/list.h>
  21 #include <linux/kernel.h>
  22 #include <linux/mm.h>
  23 #include <linux/module.h>
  24 #include <linux/net.h>
  25 #include <net/sock.h>
  26
  27 struct aead_sg_list {
  28         unsigned int cur;
  29         struct scatterlist sg[ALG_MAX_PAGES];
  30 };
  31
  32 struct aead_async_rsgl {
  33         struct af_alg_sgl sgl;
  34         struct list_head list;
  35 };
  36
  37 struct aead_async_req {
  38         struct scatterlist *tsgl;
  39         struct aead_async_rsgl first_rsgl;
  40         struct list_head list;
  41         struct kiocb *iocb;
  42         unsigned int tsgls;
  43         char iv[];
  44 };
  45
  46 struct aead_ctx {
  47         struct aead_sg_list tsgl;
  48         struct aead_async_rsgl first_rsgl;
  49         struct list_head list;
  50
  51         void *iv;
  52
  53         struct af_alg_completion completion;
  54
  55         unsigned long used;
  56
  57         unsigned int len;
  58         bool more;
  59         bool merge;
  60         bool enc;
  61
  62         size_t aead_assoclen;
  63         struct aead_request aead_req;
  64 };
  65
  66 static inline int aead_sndbuf(struct sock *sk)
  67 {
  68         struct alg_sock *ask = alg_sk(sk);
  69         struct aead_ctx *ctx = ask->private;
  70
  71         return max_t(int, max_t(int, sk->sk_sndbuf & PAGE_MASK, PAGE_SIZE) -
  72                           ctx->used, 0);
  73 }
  74
  75 static inline bool aead_writable(struct sock *sk)
  76 {
  77         return PAGE_SIZE <= aead_sndbuf(sk);
  78 }
  79
  80 static inline bool aead_sufficient_data(struct aead_ctx *ctx)
  81 {
  82         unsigned as = crypto_aead_authsize(crypto_aead_reqtfm(&ctx->aead_req));
  83
  84         /*
  85          * The minimum amount of memory needed for an AEAD cipher is
  86          * the AAD and in case of decryption the tag.
  87          */
  88         return ctx->used >= ctx->aead_assoclen + (ctx->enc ? 0 : as);
  89 }
  90
  91 static void aead_reset_ctx(struct aead_ctx *ctx)
  92 {
  93         struct aead_sg_list *sgl = &ctx->tsgl;
  94
  95         sg_init_table(sgl->sg, ALG_MAX_PAGES);
  96         sgl->cur = 0;
  97         ctx->used = 0;
  98         ctx->more = 0;
  99         ctx->merge = 0;
 100 }
 101
 102 static void aead_put_sgl(struct sock *sk)
 103 {
 104         struct alg_sock *ask = alg_sk(sk);
 105         struct aead_ctx *ctx = ask->private;
 106         struct aead_sg_list *sgl = &ctx->tsgl;
 107         struct scatterlist *sg = sgl->sg;
 108         unsigned int i;
 109
 110         for (i = 0; i < sgl->cur; i++) {
 111                 if (!sg_page(sg + i))
 112                         continue;
 113
 114                 put_page(sg_page(sg + i));
 115                 sg_assign_page(sg + i, NULL);
 116         }
 117         aead_reset_ctx(ctx);
 118 }
 119
 120 static void aead_wmem_wakeup(struct sock *sk)
 121 {
 122         struct socket_wq *wq;
 123
 124         if (!aead_writable(sk))
 125                 return;
 126
 127         rcu_read_lock();
 128         wq = rcu_dereference(sk->sk_wq);
 129         if (skwq_has_sleeper(wq))
 130                 wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
 131                                                            POLLRDNORM |
 132                                                            POLLRDBAND);
 133         sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
 134         rcu_read_unlock();
 135 }
 136
 137 static int aead_wait_for_data(struct sock *sk, unsigned flags)
 138 {
 139         DEFINE_WAIT_FUNC(wait, woken_wake_function);
 140         struct alg_sock *ask = alg_sk(sk);
 141         struct aead_ctx *ctx = ask->private;
 142         long timeout;
 143         int err = -ERESTARTSYS;
 144
 145         if (flags & MSG_DONTWAIT)
 146                 return -EAGAIN;
 147
 148         sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
 149         add_wait_queue(sk_sleep(sk), &wait);
 150         for (;;) {
 151                 if (signal_pending(current))
 152                         break;
 153                 timeout = MAX_SCHEDULE_TIMEOUT;
 154                 if (sk_wait_event(sk, &timeout, !ctx->more, &wait)) {
 155                         err = 0;
 156                         break;
 157                 }
 158         }
 159         remove_wait_queue(sk_sleep(sk), &wait);
 160
 161         sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
 162
 163         return err;
 164 }
 165
 166 static void aead_data_wakeup(struct sock *sk)
 167 {
 168         struct alg_sock *ask = alg_sk(sk);
 169         struct aead_ctx *ctx = ask->private;
 170         struct socket_wq *wq;
 171
 172         if (ctx->more)
 173                 return;
 174         if (!ctx->used)
 175                 return;
 176
 177         rcu_read_lock();
 178         wq = rcu_dereference(sk->sk_wq);
 179         if (skwq_has_sleeper(wq))
 180                 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
 181                                                            POLLRDNORM |
 182                                                            POLLRDBAND);
 183         sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
 184         rcu_read_unlock();
 185 }
 186
 187 static int aead_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 188 {
 189         struct sock *sk = sock->sk;
 190         struct alg_sock *ask = alg_sk(sk);
 191         struct aead_ctx *ctx = ask->private;
 192         unsigned ivsize =
 193                 crypto_aead_ivsize(crypto_aead_reqtfm(&ctx->aead_req));
 194         struct aead_sg_list *sgl = &ctx->tsgl;
 195         struct af_alg_control con = {};
 196         long copied = 0;
 197         bool enc = 0;
 198         bool init = 0;
 199         int err = -EINVAL;
 200
 201         if (msg->msg_controllen) {
 202                 err = af_alg_cmsg_send(msg, &con);
 203                 if (err)
 204                         return err;
 205
 206                 init = 1;
 207                 switch (con.op) {
 208                 case ALG_OP_ENCRYPT:
 209                         enc = 1;
 210                         break;
 211                 case ALG_OP_DECRYPT:
 212                         enc = 0;
 213                         break;
 214                 default:
 215                         return -EINVAL;
 216                 }
 217
 218                 if (con.iv && con.iv->ivlen != ivsize)
 219                         return -EINVAL;
 220         }
 221
 222         lock_sock(sk);
 223         if (!ctx->more && ctx->used)
 224                 goto unlock;
 225
 226         if (init) {
 227                 ctx->enc = enc;
 228                 if (con.iv)
 229                         memcpy(ctx->iv, con.iv->iv, ivsize);
 230
 231                 ctx->aead_assoclen = con.aead_assoclen;
 232         }
 233
 234         while (size) {
 235                 size_t len = size;
 236                 struct scatterlist *sg = NULL;
 237
 238                 /* use the existing memory in an allocated page */
 239                 if (ctx->merge) {
 240                         sg = sgl->sg + sgl->cur - 1;
 241                         len = min_t(unsigned long, len,
 242                                     PAGE_SIZE - sg->offset - sg->length);
 243                         err = memcpy_from_msg(page_address(sg_page(sg)) +
 244                                               sg->offset + sg->length,
 245                                               msg, len);
 246                         if (err)
 247                                 goto unlock;
 248
 249                         sg->length += len;
 250                         ctx->merge = (sg->offset + sg->length) &
 251                                      (PAGE_SIZE - 1);
 252
 253                         ctx->used += len;
 254                         copied += len;
 255                         size -= len;
 256                         continue;
 257                 }
 258
 259                 if (!aead_writable(sk)) {
 260                         /* user space sent too much data */
 261                         aead_put_sgl(sk);
 262                         err = -EMSGSIZE;
 263                         goto unlock;
 264                 }
 265
 266                 /* allocate a new page */
 267                 len = min_t(unsigned long, size, aead_sndbuf(sk));
 268                 while (len) {
 269                         size_t plen = 0;
 270
 271                         if (sgl->cur >= ALG_MAX_PAGES) {
 272                                 aead_put_sgl(sk);
 273                                 err = -E2BIG;
 274                                 goto unlock;
 275                         }
 276
 277                         sg = sgl->sg + sgl->cur;
 278                         plen = min_t(size_t, len, PAGE_SIZE);
 279
 280                         sg_assign_page(sg, alloc_page(GFP_KERNEL));
 281                         err = -ENOMEM;
 282                         if (!sg_page(sg))
 283                                 goto unlock;
 284
 285                         err = memcpy_from_msg(page_address(sg_page(sg)),
 286                                               msg, plen);
 287                         if (err) {
 288                                 __free_page(sg_page(sg));
 289                                 sg_assign_page(sg, NULL);
 290                                 goto unlock;
 291                         }
 292
 293                         sg->offset = 0;
 294                         sg->length = plen;
 295                         len -= plen;
 296                         ctx->used += plen;
 297                         copied += plen;
 298                         sgl->cur++;
 299                         size -= plen;
 300                         ctx->merge = plen & (PAGE_SIZE - 1);
 301                 }
 302         }
 303
 304         err = 0;
 305
 306         ctx->more = msg->msg_flags & MSG_MORE;
 307         if (!ctx->more && !aead_sufficient_data(ctx)) {
 308                 aead_put_sgl(sk);
 309                 err = -EMSGSIZE;
 310         }
 311
 312 unlock:
 313         aead_data_wakeup(sk);
 314         release_sock(sk);
 315
 316         return err ?: copied;
 317 }
 318
 319 static ssize_t aead_sendpage(struct socket *sock, struct page *page,
 320                              int offset, size_t size, int flags)
 321 {
 322         struct sock *sk = sock->sk;
 323         struct alg_sock *ask = alg_sk(sk);
 324         struct aead_ctx *ctx = ask->private;
 325         struct aead_sg_list *sgl = &ctx->tsgl;
 326         int err = -EINVAL;
 327
 328         if (flags & MSG_SENDPAGE_NOTLAST)
 329                 flags |= MSG_MORE;
 330
 331         if (sgl->cur >= ALG_MAX_PAGES)
 332                 return -E2BIG;
 333
 334         lock_sock(sk);
 335         if (!ctx->more && ctx->used)
 336                 goto unlock;
 337
 338         if (!size)
 339                 goto done;
 340
 341         if (!aead_writable(sk)) {
 342                 /* user space sent too much data */
 343                 aead_put_sgl(sk);
 344                 err = -EMSGSIZE;
 345                 goto unlock;
 346         }
 347
 348         ctx->merge = 0;
 349
 350         get_page(page);
 351         sg_set_page(sgl->sg + sgl->cur, page, size, offset);
 352         sgl->cur++;
 353         ctx->used += size;
 354
 355         err = 0;
 356
 357 done:
 358         ctx->more = flags & MSG_MORE;
 359         if (!ctx->more && !aead_sufficient_data(ctx)) {
 360                 aead_put_sgl(sk);
 361                 err = -EMSGSIZE;
 362         }
 363
 364 unlock:
 365         aead_data_wakeup(sk);
 366         release_sock(sk);
 367
 368         return err ?: size;
 369 }
 370
 371 #define GET_ASYM_REQ(req, tfm) (struct aead_async_req *) \
 372                 ((char *)req + sizeof(struct aead_request) + \
 373                  crypto_aead_reqsize(tfm))
 374
 375  #define GET_REQ_SIZE(tfm) sizeof(struct aead_async_req) + \
 376         crypto_aead_reqsize(tfm) + crypto_aead_ivsize(tfm) + \
 377         sizeof(struct aead_request)
 378
 379 static void aead_async_cb(struct crypto_async_request *_req, int err)
 380 {
 381         struct sock *sk = _req->data;
 382         struct alg_sock *ask = alg_sk(sk);
 383         struct aead_ctx *ctx = ask->private;
 384         struct crypto_aead *tfm = crypto_aead_reqtfm(&ctx->aead_req);
 385         struct aead_request *req = aead_request_cast(_req);
 386         struct aead_async_req *areq = GET_ASYM_REQ(req, tfm);
 387         struct scatterlist *sg = areq->tsgl;
 388         struct aead_async_rsgl *rsgl;
 389         struct kiocb *iocb = areq->iocb;
 390         unsigned int i, reqlen = GET_REQ_SIZE(tfm);
 391
 392         list_for_each_entry(rsgl, &areq->list, list) {
 393                 af_alg_free_sg(&rsgl->sgl);
 394                 if (rsgl != &areq->first_rsgl)
 395                         sock_kfree_s(sk, rsgl, sizeof(*rsgl));
 396         }
 397
 398         for (i = 0; i < areq->tsgls; i++)
 399                 put_page(sg_page(sg + i));
 400
 401         sock_kfree_s(sk, areq->tsgl, sizeof(*areq->tsgl) * areq->tsgls);
 402         sock_kfree_s(sk, req, reqlen);
 403         __sock_put(sk);
 404         iocb->ki_complete(iocb, err, err);
 405 }
 406
 407 static int aead_recvmsg_async(struct socket *sock, struct msghdr *msg,
 408                               int flags)
 409 {
 410         struct sock *sk = sock->sk;
 411         struct alg_sock *ask = alg_sk(sk);
 412         struct aead_ctx *ctx = ask->private;
 413         struct crypto_aead *tfm = crypto_aead_reqtfm(&ctx->aead_req);
 414         struct aead_async_req *areq;
 415         struct aead_request *req = NULL;
 416         struct aead_sg_list *sgl = &ctx->tsgl;
 417         struct aead_async_rsgl *last_rsgl = NULL, *rsgl;
 418         unsigned int as = crypto_aead_authsize(tfm);
 419         unsigned int i, reqlen = GET_REQ_SIZE(tfm);
 420         int err = -ENOMEM;
 421         unsigned long used;
 422         size_t outlen = 0;
 423         size_t usedpages = 0;
 424
 425         lock_sock(sk);
 426         if (ctx->more) {
 427                 err = aead_wait_for_data(sk, flags);
 428                 if (err)
 429                         goto unlock;
 430         }
 431
 432         if (!aead_sufficient_data(ctx))
 433                 goto unlock;
 434
 435         used = ctx->used;
 436         if (ctx->enc)
 437                 outlen = used + as;
 438         else
 439                 outlen = used - as;
 440
 441         req = sock_kmalloc(sk, reqlen, GFP_KERNEL);
 442         if (unlikely(!req))
 443                 goto unlock;
 444
 445         areq = GET_ASYM_REQ(req, tfm);
 446         memset(&areq->first_rsgl, '\0', sizeof(areq->first_rsgl));
 447         INIT_LIST_HEAD(&areq->list);
 448         areq->iocb = msg->msg_iocb;
 449         memcpy(areq->iv, ctx->iv, crypto_aead_ivsize(tfm));
 450         aead_request_set_tfm(req, tfm);
 451         aead_request_set_ad(req, ctx->aead_assoclen);
 452         aead_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
 453                                   aead_async_cb, sk);
 454         used -= ctx->aead_assoclen;
 455
 456         /* take over all tx sgls from ctx */
 457         areq->tsgl = sock_kmalloc(sk,
 458                                   sizeof(*areq->tsgl) * max_t(u32, sgl->cur, 1),
 459                                   GFP_KERNEL);
 460         if (unlikely(!areq->tsgl))
 461                 goto free;
 462
 463         sg_init_table(areq->tsgl, max_t(u32, sgl->cur, 1));
 464         for (i = 0; i < sgl->cur; i++)
 465                 sg_set_page(&areq->tsgl[i], sg_page(&sgl->sg[i]),
 466                             sgl->sg[i].length, sgl->sg[i].offset);
 467
 468         areq->tsgls = sgl->cur;
 469
 470         /* create rx sgls */
 471         while (outlen > usedpages && iov_iter_count(&msg->msg_iter)) {
 472                 size_t seglen = min_t(size_t, iov_iter_count(&msg->msg_iter),
 473                                       (outlen - usedpages));
 474
 475                 if (list_empty(&areq->list)) {
 476                         rsgl = &areq->first_rsgl;
 477
 478                 } else {
 479                         rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL);
 480                         if (unlikely(!rsgl)) {
 481                                 err = -ENOMEM;
 482                                 goto free;
 483                         }
 484                 }
 485                 rsgl->sgl.npages = 0;
 486                 list_add_tail(&rsgl->list, &areq->list);
 487
 488                 /* make one iovec available as scatterlist */
 489                 err = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, seglen);
 490                 if (err < 0)
 491                         goto free;
 492
 493                 usedpages += err;
 494
 495                 /* chain the new scatterlist with previous one */
 496                 if (last_rsgl)
 497                         af_alg_link_sg(&last_rsgl->sgl, &rsgl->sgl);
 498
 499                 last_rsgl = rsgl;
 500
 501                 iov_iter_advance(&msg->msg_iter, err);
 502         }
 503
 504         /* ensure output buffer is sufficiently large */
 505         if (usedpages < outlen) {
 506                 err = -EINVAL;
 507                 goto unlock;
 508         }
 509
 510         aead_request_set_crypt(req, areq->tsgl, areq->first_rsgl.sgl.sg, used,
 511                                areq->iv);
 512         err = ctx->enc ? crypto_aead_encrypt(req) : crypto_aead_decrypt(req);
 513         if (err) {
 514                 if (err == -EINPROGRESS) {
 515                         sock_hold(sk);
 516                         err = -EIOCBQUEUED;
 517                         aead_reset_ctx(ctx);
 518                         goto unlock;
 519                 } else if (err == -EBADMSG) {
 520                         aead_put_sgl(sk);
 521                 }
 522                 goto free;
 523         }
 524         aead_put_sgl(sk);
 525
 526 free:
 527         list_for_each_entry(rsgl, &areq->list, list) {
 528                 af_alg_free_sg(&rsgl->sgl);
 529                 if (rsgl != &areq->first_rsgl)
 530                         sock_kfree_s(sk, rsgl, sizeof(*rsgl));
 531         }
 532         if (areq->tsgl)
 533                 sock_kfree_s(sk, areq->tsgl, sizeof(*areq->tsgl) * areq->tsgls);
 534         if (req)
 535                 sock_kfree_s(sk, req, reqlen);
 536 unlock:
 537         aead_wmem_wakeup(sk);
 538         release_sock(sk);
 539         return err ? err : outlen;
 540 }
 541
 542 static int aead_recvmsg_sync(struct socket *sock, struct msghdr *msg, int flags)
 543 {
 544         struct sock *sk = sock->sk;
 545         struct alg_sock *ask = alg_sk(sk);
 546         struct aead_ctx *ctx = ask->private;
 547         unsigned as = crypto_aead_authsize(crypto_aead_reqtfm(&ctx->aead_req));
 548         struct aead_sg_list *sgl = &ctx->tsgl;
 549         struct aead_async_rsgl *last_rsgl = NULL;
 550         struct aead_async_rsgl *rsgl, *tmp;
 551         int err = -EINVAL;
 552         unsigned long used = 0;
 553         size_t outlen = 0;
 554         size_t usedpages = 0;
 555
 556         lock_sock(sk);
 557
 558         /*
 559          * Please see documentation of aead_request_set_crypt for the
 560          * description of the AEAD memory structure expected from the caller.
 561          */
 562
 563         if (ctx->more) {
 564                 err = aead_wait_for_data(sk, flags);
 565                 if (err)
 566                         goto unlock;
 567         }
 568
 569         /* data length provided by caller via sendmsg/sendpage */
 570         used = ctx->used;
 571
 572         /*
 573          * Make sure sufficient data is present -- note, the same check is
 574          * is also present in sendmsg/sendpage. The checks in sendpage/sendmsg
 575          * shall provide an information to the data sender that something is
 576          * wrong, but they are irrelevant to maintain the kernel integrity.
 577          * We need this check here too in case user space decides to not honor
 578          * the error message in sendmsg/sendpage and still call recvmsg. This
 579          * check here protects the kernel integrity.
 580          */
 581         if (!aead_sufficient_data(ctx))
 582                 goto unlock;
 583
 584         /*
 585          * Calculate the minimum output buffer size holding the result of the
 586          * cipher operation. When encrypting data, the receiving buffer is
 587          * larger by the tag length compared to the input buffer as the
 588          * encryption operation generates the tag. For decryption, the input
 589          * buffer provides the tag which is consumed resulting in only the
 590          * plaintext without a buffer for the tag returned to the caller.
 591          */
 592         if (ctx->enc)
 593                 outlen = used + as;
 594         else
 595                 outlen = used - as;
 596
 597         /*
 598          * The cipher operation input data is reduced by the associated data
 599          * length as this data is processed separately later on.
 600          */
 601         used -= ctx->aead_assoclen;
 602
 603         /* convert iovecs of output buffers into scatterlists */
 604         while (outlen > usedpages && iov_iter_count(&msg->msg_iter)) {
 605                 size_t seglen = min_t(size_t, iov_iter_count(&msg->msg_iter),
 606                                       (outlen - usedpages));
 607
 608                 if (list_empty(&ctx->list)) {
 609                         rsgl = &ctx->first_rsgl;
 610                 } else {
 611                         rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL);
 612                         if (unlikely(!rsgl)) {
 613                                 err = -ENOMEM;
 614                                 goto unlock;
 615                         }
 616                 }
 617                 rsgl->sgl.npages = 0;
 618                 list_add_tail(&rsgl->list, &ctx->list);
 619
 620                 /* make one iovec available as scatterlist */
 621                 err = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, seglen);
 622                 if (err < 0)
 623                         goto unlock;
 624                 usedpages += err;
 625                 /* chain the new scatterlist with previous one */
 626                 if (last_rsgl)
 627                         af_alg_link_sg(&last_rsgl->sgl, &rsgl->sgl);
 628
 629                 last_rsgl = rsgl;
 630
 631                 iov_iter_advance(&msg->msg_iter, err);
 632         }
 633
 634         /* ensure output buffer is sufficiently large */
 635         if (usedpages < outlen) {
 636                 err = -EINVAL;
 637                 goto unlock;
 638         }
 639
 640         sg_mark_end(sgl->sg + sgl->cur - 1);
 641         aead_request_set_crypt(&ctx->aead_req, sgl->sg, ctx->first_rsgl.sgl.sg,
 642                                used, ctx->iv);
 643         aead_request_set_ad(&ctx->aead_req, ctx->aead_assoclen);
 644
 645         err = af_alg_wait_for_completion(ctx->enc ?
 646                                          crypto_aead_encrypt(&ctx->aead_req) :
 647                                          crypto_aead_decrypt(&ctx->aead_req),
 648                                          &ctx->completion);
 649
 650         if (err) {
 651                 /* EBADMSG implies a valid cipher operation took place */
 652                 if (err == -EBADMSG)
 653                         aead_put_sgl(sk);
 654
 655                 goto unlock;
 656         }
 657
 658         aead_put_sgl(sk);
 659         err = 0;
 660
 661 unlock:
 662         list_for_each_entry_safe(rsgl, tmp, &ctx->list, list) {
 663                 af_alg_free_sg(&rsgl->sgl);
 664                 list_del(&rsgl->list);
 665                 if (rsgl != &ctx->first_rsgl)
 666                         sock_kfree_s(sk, rsgl, sizeof(*rsgl));
 667         }
 668         INIT_LIST_HEAD(&ctx->list);
 669         aead_wmem_wakeup(sk);
 670         release_sock(sk);
 671
 672         return err ? err : outlen;
 673 }
 674
 675 static int aead_recvmsg(struct socket *sock, struct msghdr *msg, size_t ignored,
 676                         int flags)
 677 {
 678         return (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) ?
 679                 aead_recvmsg_async(sock, msg, flags) :
 680                 aead_recvmsg_sync(sock, msg, flags);
 681 }
 682
 683 static unsigned int aead_poll(struct file *file, struct socket *sock,
 684                               poll_table *wait)
 685 {
 686         struct sock *sk = sock->sk;
 687         struct alg_sock *ask = alg_sk(sk);
 688         struct aead_ctx *ctx = ask->private;
 689         unsigned int mask;
 690
 691         sock_poll_wait(file, sk_sleep(sk), wait);
 692         mask = 0;
 693
 694         if (!ctx->more)
 695                 mask |= POLLIN | POLLRDNORM;
 696
 697         if (aead_writable(sk))
 698                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
 699
 700         return mask;
 701 }
 702
 703 static struct proto_ops algif_aead_ops = {
 704         .family         =       PF_ALG,
 705
 706         .connect        =       sock_no_connect,
 707         .socketpair     =       sock_no_socketpair,
 708         .getname        =       sock_no_getname,
 709         .ioctl          =       sock_no_ioctl,
 710         .listen         =       sock_no_listen,
 711         .shutdown       =       sock_no_shutdown,
 712         .getsockopt     =       sock_no_getsockopt,
 713         .mmap           =       sock_no_mmap,
 714         .bind           =       sock_no_bind,
 715         .accept         =       sock_no_accept,
 716         .setsockopt     =       sock_no_setsockopt,
 717
 718         .release        =       af_alg_release,
 719         .sendmsg        =       aead_sendmsg,
 720         .sendpage       =       aead_sendpage,
 721         .recvmsg        =       aead_recvmsg,
 722         .poll           =       aead_poll,
 723 };
 724
 725 static void *aead_bind(const char *name, u32 type, u32 mask)
 726 {
 727         return crypto_alloc_aead(name, type, mask);
 728 }
 729
 730 static void aead_release(void *private)
 731 {
 732         crypto_free_aead(private);
 733 }
 734
 735 static int aead_setauthsize(void *private, unsigned int authsize)
 736 {
 737         return crypto_aead_setauthsize(private, authsize);
 738 }
 739
 740 static int aead_setkey(void *private, const u8 *key, unsigned int keylen)
 741 {
 742         return crypto_aead_setkey(private, key, keylen);
 743 }
 744
 745 static void aead_sock_destruct(struct sock *sk)
 746 {
 747         struct alg_sock *ask = alg_sk(sk);
 748         struct aead_ctx *ctx = ask->private;
 749         unsigned int ivlen = crypto_aead_ivsize(
 750                                 crypto_aead_reqtfm(&ctx->aead_req));
 751
 752         WARN_ON(atomic_read(&sk->sk_refcnt) != 0);
 753         aead_put_sgl(sk);
 754         sock_kzfree_s(sk, ctx->iv, ivlen);
 755         sock_kfree_s(sk, ctx, ctx->len);
 756         af_alg_release_parent(sk);
 757 }
 758
 759 static int aead_accept_parent(void *private, struct sock *sk)
 760 {
 761         struct aead_ctx *ctx;
 762         struct alg_sock *ask = alg_sk(sk);
 763         unsigned int len = sizeof(*ctx) + crypto_aead_reqsize(private);
 764         unsigned int ivlen = crypto_aead_ivsize(private);
 765
 766         ctx = sock_kmalloc(sk, len, GFP_KERNEL);
 767         if (!ctx)
 768                 return -ENOMEM;
 769         memset(ctx, 0, len);
 770
 771         ctx->iv = sock_kmalloc(sk, ivlen, GFP_KERNEL);
 772         if (!ctx->iv) {
 773                 sock_kfree_s(sk, ctx, len);
 774                 return -ENOMEM;
 775         }
 776         memset(ctx->iv, 0, ivlen);
 777
 778         ctx->len = len;
 779         ctx->used = 0;
 780         ctx->more = 0;
 781         ctx->merge = 0;
 782         ctx->enc = 0;
 783         ctx->tsgl.cur = 0;
 784         ctx->aead_assoclen = 0;
 785         af_alg_init_completion(&ctx->completion);
 786         sg_init_table(ctx->tsgl.sg, ALG_MAX_PAGES);
 787         INIT_LIST_HEAD(&ctx->list);
 788
 789         ask->private = ctx;
 790
 791         aead_request_set_tfm(&ctx->aead_req, private);
 792         aead_request_set_callback(&ctx->aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG,
 793                                   af_alg_complete, &ctx->completion);
 794
 795         sk->sk_destruct = aead_sock_destruct;
 796
 797         return 0;
 798 }
 799
 800 static const struct af_alg_type algif_type_aead = {
 801         .bind           =       aead_bind,
 802         .release        =       aead_release,
 803         .setkey         =       aead_setkey,
 804         .setauthsize    =       aead_setauthsize,
 805         .accept         =       aead_accept_parent,
 806         .ops            =       &algif_aead_ops,
 807         .name           =       "aead",
 808         .owner          =       THIS_MODULE
 809 };
 810
 811 static int __init algif_aead_init(void)
 812 {
 813         return af_alg_register_type(&algif_type_aead);
 814 }
 815
 816 static void __exit algif_aead_exit(void)
 817 {
 818         int err = af_alg_unregister_type(&algif_type_aead);
 819         BUG_ON(err);
 820 }
 821
 822 module_init(algif_aead_init);
 823 module_exit(algif_aead_exit);
 824 MODULE_LICENSE("GPL");
 825 MODULE_AUTHOR("Stephan Mueller <smueller@chronox.de>");
 826 MODULE_DESCRIPTION("AEAD kernel crypto API user space interface");